I. Field of the Invention
The present invention relates to oxygen flame cutting and welding apparatus and more particularly to a new ignition means for such apparatus.
II. Description of the Prior Art
In oxygen flame cutting and welding apparatus an ignition device is provided near the flame to provide the necessary heat for joining or separating the workpiece. Generally such a device takes the form of iron either as a wire or as a powder which as it combines with the oxygen melts to create heat at the working face.
This process is especially useful with high temperature alloys where without this method it would be virtually impossible to create the heat necessary to join or to separate the materials.
Previously either an iron wire or iron powder has been used as the ignition means. Where iron powder is used it generally is directed to the point of the flame by compressed air or any other dry gas.
While such an ignition means has proven generally satisfactory it requires equipment which is subject to breakdowns. It creates storage and transportation problems with respect to the powder and the equipment is generally bulky and expensive.
Prior art ignition devices have also taken the form of wire held on a reel and moved into the flame in step-by-step fashion. Powder is more suitable for some materials and thus this form of ignition device is not satisfactory for all processes. Further, on automatic equipment the wire must go through straightening rollers to insure that there are no kinks and bends. Bends in the wire will cause the apparatus to jam up which in turn can cause the wire to melt back to the holder, heating it to a dangerous level, and even causing it to be fused together and damaged by the heat.
Straightening rollers will not insure that all bends will be removed from the wire and if it is corroded or rusty it can still become jammed.
Short individual ignition rods can also be used but heretofore this has created waste because not all of the rod could be used. The use of such rods with automatic equipment was not heretofore possible. The feed device would have to be very near the flame because of the shortness of the rod which again could cause the feed device to be unduly heated and thereby damaged.